The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
An autonomous vehicle travels to a destination by itself even if a driver does not operate a steering wheel, an accelerator pedal, or a brake pedal. The autonomous vehicle is actually different from an unmanned vehicle traveling without a driver, but in these days, the terms “autonomous vehicle” and “unmanned vehicle” are used without distinction.
An example of autonomous driving is automatic parking. The automatic parking means that the autonomous vehicle itself finds empty parking space to perform parking by itself. To achieve the automatic parking, the autonomous vehicle should be equipped with three-dimensional environment recognition technology to detect surrounding geographic features and objects.
In order to detect geographical features and objects, a detection device, such as a binocular stereo camera, a radar, a lidar, and an ultrasonic sensor, is needed. However, the binocular stereo camera, the radar, and the lidar are expensive. Also, the ultrasonic sensor has difficulties in acquiring additional information, and has a short detection range.